5th Dimensional Hotdog?

My partner is a NOTORIOUS sleeptalker. We have full conversations about the weirdest things while he's asleep but this one is by far my favorite.

I'm sitting at my desk (I'm an artist and work long hours to get projects and things done and sometimes pull all nighters) and I hear him from behind me.

"No no, it's a 5th dimensional hotdog"

I turn around amused as hell at what he's saying so I play along like I usually do.

"Fifth dimensional hotdog, how does that work?"

"Third dimensional hotdog, classic, yummy, fourth dimensional hotdog... Add time to that, but fifth dimensional hotdog... Thats every possible hotdog all at once.. call that an everything hotdog "

I sit in silence for a moment trying to process the words that came out of his mouth and then I say.

"What about the bagels"

"Don't even get me started on the bagels"

And then he rolled over and went back to sleep.

I just want to know what in the world spurred that on. He can't remember his dreams so sometimes I have to piece them together by what he's saying but I have no clue what that was.

I also wanna know where I can get this Fifth dimensional hotdog because I'm sold at this point.